The only 7.3 I owned was an '89 Super Duty that had probably 200k on it and it hated weather below 50. I put new glow plugs in it and it still wouldn't start if it wasn't plugged in. I had an '04 6.0 that had 250k before I had to replace 4 glow plugs so there definitely better than the old 7.3s and 6.9s, I heard you had change those about every winter. I really liked my 6.0, had to spend some money on it like all of them but I never had a programmer on it and never had the head gasket issues or blew the motor up. I drove it for 12 years and I've never kept a truck that long. Didn't really want to sell it but I figured I better because I would never be able to get the money I got for it again!Yeah I owned a 6.9l, a 7.3l IDI, a 7.3l and a 6.0l before my 6.7l. The 7.3l and 6.0l will start at zero or just below without being plugged in. The 6.9l and 7.3lIDI wouldn't for me.